The 1.0-litre EcoBoost engine is the most popular version in Europe, and last year became the first to be named International Engine of the Year for a third time in a row.
"Ford EcoBoost delivers great performance with lower fuel bills, a recipe which is proving incredibly popular with consumers in Europe and around the world," states Joe Bakaj, vice president of product development for Ford of Europe.
"EcoBoost engines have proved a game-changing technology that is attracting new customers to the Ford brand every day."
The five millionth vehicle was a 1.0-litre Ford Focus that rolled off the assembly line at the Michigan assembly plant, in the US.
Worldwide, every month, more than 200,000 EcoBoost engines are produced – including 1.5-litre, 1.6-litre, 2.0-litre and 2.3-litre four-cylinder engines, and 2.7-litre and 3.5-litre V6 engines.
The Ford Bridgend plant in Wales in the UK produces 1.5- and 1.6-litre EcoBoost engines.